Physiological response of bread wheat production triticum aestivum L. ssp. aestivum

Abstract

Objective: To evaluate the physiological response of bread wheat (Triticum aestivum L. ssp. aestivum) production under water deficit. Methodology: Physiological variables were evaluated during the different phenological stages of the crop, along with morphological evaluations, yield, and grain quality of four genotypes (Centenario, El Nazareno, EEATH-122, and PITH 34), in two environments (irrigated and water deficit), using a randomized block design in each environment, where each experimental unit consisted of seven m², with a spacing of 0.35 m between rows. For the experiment, a gravity irrigation system was used, monitored with moisture sensors in both environments throughout the crop phenology. In the environment subjected to water deficit, irrigation was restricted from the 20th day after sowing (DAS); whereas in the irrigated environment, it was applied according to need. The soil was clay-textured, and fertilization was applied prior to sowing. Results: An important effect was observed in all genotypes under water deficit conditions, where the values of chlorophyll content, stomatal conductance, normalized vegetation index, and relative leaf water content were lower, while canopy temperature was higher compared to the irrigated environment. Likewise, it was observed that all genotypes subjected to water deficit reached physiological maturity in a significantly shorter time (10.65%), with up to 50% yield reduction, plants 12.22% smaller, spikes 9.76% shorter, with 11.87% fewer grains and 13.08% lower protein content. Conclusion: After the combined analysis, no interaction between treatments and environment was observed, only differences between the environments.